<!DOCTYPE html>
<html>

	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>

	<body>
		<script>
			var a = 1;

			var obj = {
				b: 2
			};
			var fn = function() {};
			fn.c = 3;

			function test(x, y, z) {
				x = 4;
				y.b = 5;
				z.c = 6;
				//return z;
				console.log(x);
			}
			test(a, obj, fn);
			//alert(a + obj.b + fn.c);
		</script>
	</body>

</html>